From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=0.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLACK autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 90A93C433E0 for ; Tue, 9 Jun 2020 20:34:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 60F6320737 for ; Tue, 9 Jun 2020 20:34:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728553AbgFIUeZ (ORCPT ); Tue, 9 Jun 2020 16:34:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38692 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728012AbgFIUeT (ORCPT ); Tue, 9 Jun 2020 16:34:19 -0400 Received: from Galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 248F1C05BD1E for ; Tue, 9 Jun 2020 13:34:19 -0700 (PDT) Received: from p5de0bf0b.dip0.t-ipconnect.de ([93.224.191.11] helo=nanos.tec.linutronix.de) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1jikwK-00014U-HN; Tue, 09 Jun 2020 22:33:44 +0200 Received: by nanos.tec.linutronix.de (Postfix, from userid 1000) id BBE9F10154A; Tue, 9 Jun 2020 22:33:43 +0200 (CEST) From: Thomas Gleixner To: Qian Cai Cc: Peter Zijlstra , LKML , Andy Lutomirski , Andrew Cooper , X86 ML , "Paul E. McKenney" , Alexandre Chartre , Frederic Weisbecker , Paolo Bonzini , Sean Christopherson , Masami Hiramatsu , Petr Mladek , Steven Rostedt , Joel Fernandes , Boris Ostrovsky , Juergen Gross , Brian Gerst , Mathieu Desnoyers , Josh Poimboeuf , Will Deacon , Tom Lendacky , Wei Liu , Michael Kelley , Jason Chen CJ , Zhao Yakui , Alexander Potapenko Subject: Re: [patch V9 10/39] x86/entry: Provide helpers for execute on irqstack In-Reply-To: <20200609023259.GA3579@lca.pw> Date: Tue, 09 Jun 2020 22:33:43 +0200 Message-ID: <87zh9cnfmg.fsf@nanos.tec.linutronix.de> MIME-Version: 1.0 Content-Type: text/plain X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Qian, Qian Cai writes: > On Tue, Jun 09, 2020 at 12:20:06AM +0200, Thomas Gleixner wrote: >> Note, that I doubled the size of the stack depot so that we get real >> numbers and not the cutoff by the size limit. IOW, the warning should >> not trigger anymore. If it triggers nevertheless then the numbers will >> still tell us an interesting story. > > Instead of running the whole testsuite, I just picked this single LTP > oom02 test which seems usually trigger it within the testsuite. Let me > know if this is insufficient (which indeed tell the big difference in > "Unique stacks"), and I am happy to run the whole things. thanks for providing the data. > BAD: next-20200608 > GOOD: next-20200528 (which does not include this series) > > BAD (after boot) > # cat /sys/kernel/debug/stackdepot/info > Unique stacks: 33547 > Depot index: 359 > Depot offset: 6752 > > BAD (after oom02) > # cat /sys/kernel/debug/stackdepot/info > Unique stacks: 140476 That's indeed odd. I try to reproduce and figure out what really breaks here. Thanks, tglx